18466638 has 32 divisors (see below), whose sum is σ = 38541312. Its totient is φ = 5892000.

The previous prime is 18466633. The next prime is 18466667. The reversal of 18466638 is 83666481.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 18466638.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18466633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18295 + ... + 19277.

It is an arithmetic number, because the mean of its divisors is an integer number (1204416).

Almost surely, 2^18466638 is an apocalyptic number.

18466638 is an abundant number, since it is smaller than the sum of its proper divisors (20074674).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18466638 is a wasteful number, since it uses less digits than its factorization.

18466638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1120.

The product of its digits is 165888, while the sum is 42.

The square root of 18466638 is about 4297.2826297557. The cubic root of 18466638 is about 264.3195453439.

The spelling of 18466638 in words is "eighteen million, four hundred sixty-six thousand, six hundred thirty-eight".